Page 201 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

EXERCISE 83 : Demonstrate Plotting of V-curve

Objectives

At the end of this exercise you shall be able to:
• connect and run 3-phase synchronous motor
• vary the excitation and control the power factor at no load and full load
• plot the V-curve

Requirements

Tools/Instruments Materials
• Electrician Tool kit - 1 Set • ICTP switch 16A 500V - 1 No
• MI Voltmeter 0-500V - 1 No • Lamp holder pendent - 2 Nos
• MIAmmeter0-15A - 1 No • Lamp 250V, 60 or 100 watts bulb - 2 Nos
• MC Ammeter 0 to 2.5A - 1 No • Stranded PVC insulated wire
• MC Ammeter 0 to 15A - 1 No 7/1.5 aluminium cable - 4 m
• MC Voltmeter 0 to 250 volt - 1 No • D.P.S.T. Switch 16A, 250V - 1 No
• Power factor meter 500V 15A 0.5 lag • PVC insulated connecting cable - as reqd
to 0.5 lead - 1 No • ICDP switch 16A 250V - 1 No
• Tachometer multi-range • Graph sheet - as reqd
0-300/1000/3000 rpm - 1 No

Equipment/Machines
• Synchronous motor - 5HP 415V three phase

Procedure

TASK 1 : Connect and run 3-phase synchronous motor
1 Make the connections as shown in circuit diagram and start as 3 phase induction motor
2 Run the motor as synchronous motor by providing DC excitation to rotor near to rated synchronous speed
3 Measure the speed by tachometer.

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